Forgery of paper documents has been a major cause of corruption in several countries around the world, especially in developing regions. In these regions, many of the certain essential services such as financial systems, healthcare, governance and land records, completely rely on paper as the basic medium for storing critical information. In addition, these services use paper as the primary source for establishing identity and verifying the authenticity of information. Therefore, any form of mass paper forgery can negatively impact the functioning of essential services and affect large populations.
There have been a variety of paper watermarking solutions that have been proposed to deal with the problem of paper forgery. One prior approach is to manufacture watermarked paper that uses a special form of paper or ink material that is hard to reproduce. Another conventional approach is to use different types of lithography techniques to embed a unique watermark in paper that would be hard to remove or duplicate. One problem with both of these approaches is that all they can require expensive machinery or access to specialized paper (which can be limited and expensive). In addition, the paper and inks used in some of these techniques are likely specially prepared (using physical or chemical means) and these are often not readily available in the market.
While these watermarking techniques can offer certain security properties, they have part basic limitations that constrain their use to specific application areas such as producing currency notes, checks and official paper for government records. First, these watermarking techniques are likely expensive; hence, these techniques may not be affordable for low-cost applications such as micro-finance, healthcare projects run by small institutions or corporations which lack purchasing power. Second, these watermarking techniques embed the same watermark across a bulk collection of documents (e.g., currency notes, checks, official paper). Thus, watermarked documents of the same type are generally indistinguishable from each other. In many common applications (healthcare, finance, etc.) which use paper-based records, it can be important to distinguish individual paper documents from each other. While standard bar-coding techniques can embed a unique code into each paper, such codes can easily be reproduced and duplicated.
A paper watermarking technique of fiber fingerprinting describes using a natural randomness embedded within the fiber structure of paper to extract a unique watermark. A paper watermarking technique of a print signature describes how to use randomness in the manner in which characters are printed by a laser printer to extract a unique signature for a particular printed copy.
While both these techniques can be low cost and may provide paper distinguish ability, they have certain shortcomings which can limit their use in developing region settings. Paper-based documents are very poorly maintained in developing regions and can easily get damaged due to a variety of factors, e.g., bad storage environments, damage due to rain, crumpling of watermarked area and/or aging of the paper. The fiber fingerprints within a marked region can become badly affected when paper is damaged. Similar to the fiber structure, the print in paper can deteriorate over time or can be affected when paper gets damaged.
The print signature generally relies on the imprecision of the printers to extract its signatures; when printing technology advances, the randomness we believe tends to reduce, limiting its applicability. In addition, any paper watermarking mechanism that relies on natural properties of paper would likely operate on magnified images of small regions within the paper. Therefore, for proper watermarking, it may be important to carefully extract the image from paper.
Thus, it can be desirable to provide exemplary embodiments of method, system and computer accessible medium for providing a low cost paper water marking technique that avoids the problems encountered by the techniques in the prior art as set out above.